(07/20/17) ST. GABRIEL, La. — Louisiana sugarcane growers and consultants heard about new sugarcane varieties in the pipeline along with plant diseases and other topics on July 19 during the annual field day at the LSU AgCenter Sugar Research Station.

Two potential sugarcane varieties developed at the sugar station are moving closer to release, said AgCenter plant breeder Michael Pontif.

The variety L 11-183 is expected to be released in 2018, and L 12-201 is expected to be released in 2019 if they continue to perform well in outfield trials. Two additional U.S. Department of Agriculture sugarcane varieties are expected in 2019 as well, he said.

“Louisiana sugarcane production is on the upswing with these new varieties,” Pontif said. “We’re about to have quite a few to choose from.”

The AgCenter research program is aggressive about finding varieties resistant to mosaic disease, said AgCenter plant breeder Collins Kimbeng. The researchers have identified three clones resistant to mosaic, leaf scale and smut that will be used as parents in the crossing program, he said.

A portion of the research is supported by grower funding through from the American Sugar Cane League, he said.

Rust disease was persistent in sugarcane fields this year because of a wet, cool June, said AgCenter plant pathologist Jeff Hoy. “The rust kept coming on.”

Rust and a good crop like the same growing conditions, so the presence of rust is an indicator that the sugarcane is doing well.

“Fungicides protect yield potential,” he said. “It’s a good investment.”

Because rust is a manageable problem, the AgCenter isn’t abandoning potential new varieties because they’re susceptible.

Mosaic is the same, Hoy said. It can be managed on the farm with healthy seed cane.

AgCenter weed scientist Al Orgeron talked about controlling weeds in fallow sugarcane fields and reviewed some new products that are not yet labeled for sugarcane.

The majority of current herbicides used on sugarcane are from the 1970s, Orgeron said.

“We need to use products responsibly, and we need to use products that are labeled” for sugarcane, he said.

Two insects, the Mexican rice borer and the sugarcane borer, are continuing to be problems in Louisiana sugarcane fields, said AgCenter entomologist Blake Wilson.

The invasive Mexican rice borer from Mexico has been steadily moving east from the Rio Grande Valley in Texas into Louisiana, he said.

“It’s important to distinguish between Mexican rice borer and the sugarcane borer,” Wilson said. The Mexican rice borer has two stripes while the sugarcane borer has spots, and they have different feeding behaviors.

Sugarcane borers feed higher in the plant while Mexican rice borers feed lower in the plant as well. It’s more difficult to get an insecticide lower in the plant, he said.

The window for control of borers is the short time between when larvae appear and when the burrow into the stalks.

When yields are high and the crop is more valuable, then chemical insecticides are practical for treating for both pests. “More value in the field provides substantial benefit for spraying,” Wilson said. “It pays to manage insect pests with a more-valuable crop in the field.

Matt Foster, an LSU graduate student in the School of Plant, Environmental and Soil Sciences, is evaluating soybean varieties for use in sugarcane fields. His focus is on the Xtend soybean varieties that provide tolerance to both dicamba and glyphosate herbicides to control grassy weeds in fields between sugarcane crops.

“You have to follow label requirements carefully,” Foster said.

Jim Simon, general manager of the American Sugar Cane League, spoke about the renegotiated Mexican suspension agreement related to antidumping and countervailing duties against Mexican sugar imports into the United States.

“The trade agreement is only as good as the enforcement behind it,” Simon said.

Simon said the league funds about $1 million in research at the AgCenter Sugar Research Station and the Audubon Sugar Institute.

AgCenter entomologist Rodrigo Diaz talked about the Phragmites scale, which has damaged a considerable amount of marsh cane in Plaquemines Parish from Venice to the mouth of the Mississippi River.

Because the insect may be a danger to Louisiana crops, Diaz is inoculating sugarcane, corn, rice and sweet sorghum plants to see if the scale reproduces and damages the plants.

The scale, native to Asia, has natural enemies in three small parasitic wasps.

LSU AgCenter plant pathologist Jeff Hoy, right, talks about sugarcane diseases during the 35th annual field day at the Sugar Research Station in St. Gabriel, Louisiana, on July 19. Photo by Olivia McClure/LSU AgCenter

LSU AgCenter sugarcane breeder Collins Kimbeng, left, talks about characteristics of different sugarcane varieties during the 35th annual field day at the Sugar Research Station in St. Gabriel, Louisiana, on July 19. Photo by Olivia McClure/LSU AgCenter

LSU AgCenter entomologist Blake Wilson explains the differences between Mexican rice borers and sugarcane borers during the 35th annual field day at the Sugar Research Station in St. Gabriel, Louisiana, on July 19. Photo by Olivia McClure/LSU AgCenter